A person suffering from asthma may when suffering an asthmatic attack have rather considerable trouble in breathing, due to swelling in the bronchii and due to secretion of mucous. There are various antiasthmatic pills that are effective, but which generally are somewhat slow acting. There are also medications available for intravenous treatment which work quite rapidly, but which require administration by skilled medical personnel. For most patients the promptest, immediately-available relief is by way of an inhalant. Epinephrine or other suitable asthmatic medication is packaged with a suitable diluent in a small pressurized canister or cartridge which interfits with the mouthpiece. The patient places the mouthpiece in his mouth, and depresses the cartridge, thereby releasing a measured amount of medication which is inhaled through the mouthpiece.
Some patients do not inhale properly, and the mouthpiece may not be completely effective in cooperation with the cartridge to convert the medication into a mist which is deposited in the proper bronchial area to relieve the asthmatic attack. Often there are small droplets, rather than a mist, and this may be compounded by improper inhalation which results in much of the medication simply going into the throat and stomach where it is ineffective against the asthmatic attach.
In our prior U.S. Pat. No. 4,470,412 for "Inhalation Valve" assigned to the same assignee, Trutek Research, Inc., we provided a cylindrical chamber with a one-way valve diaphragm to be held conveniently in the hand. The previous mouthpiece is inserted into the entering end of the inhalation valve, and the opposite end is received in the patient's mouth. This inhalation valve effects a much greater efficiency in converting the medication into a mist which does the most good.
In our subsequent U.S. Pat. No. 4,534,343 for "Metered Dose Inhaler", also assigned to the same assignee, Trutek Research, Inc., we provided an upright cylindrical chamber conveniently held in one hand. An extension cylinder at the top supports a pressurized canister of broncho-dilator medication which upon manual depression dispenses a measured dose of medication. A diffuser is provided beneath the valve of the canister for improved dispersion of the medication, thus to form very small droplets and mist within the chamber. A one-way valve is provided at the bottom of the chamber to prevent exiting of the medication from the bottom, while permitting entrance of ambient air upon inhalation. A horizontally disposed mouthpiece and one-way valve are disposed adjacent the upper margin of the chamber. Following a short time delay after operation of the canister for discharge of medication, the patient inhales through this mouthpiece, and both one-way valves open, admitting air at the bottom of the chamber as the mist is withdrawn through the horizontal mouthpiece. A reversal of flow and a swirling action are produced which effect a particularly efficient misting of the medication.